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% Document Info
\author{Andrzej Krzywda (pawelpacana)}
\pdfinfo{
  /Title (rails-refactoring-recipes.pdf)
  /Creator (Cheatography)
  /Author (Andrzej Krzywda (pawelpacana))
  /Subject (Rails Refactoring Recipes Cheat Sheet)
}

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\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{C}
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    {\parbox{\dimexpr\textwidth-2\fboxsep\relax}{\noindent
        \hspace*{-6pt}\includegraphics[width=5.8cm]{/web/www.cheatography.com/public/images/cheatography_logo.pdf}}
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\begin{tabulary}{11cm}{L}
    \vspace{-2pt}\large{\bf{\textcolor{DarkBackground}{\textrm{Rails Refactoring Recipes Cheat Sheet}}}} \\
    \normalsize{by \textcolor{DarkBackground}{Andrzej Krzywda (pawelpacana)} via \textcolor{DarkBackground}{\uline{cheatography.com/20181/cs/3027/}}}
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\noindent
\begin{multicols}{3}
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  \mymulticolumn{2}{p{5.377cm}}{\bf\textcolor{white}{Cheatographer}}  \\
  \vspace{-2pt}Andrzej Krzywda (pawelpacana) \\
  \uline{cheatography.com/pawelpacana} \\
        \uline{\seqsplit{rails-refactoring}.com/recipes}
  \end{tabulary}
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  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Cheat Sheet}}  \\
   \vspace{-2pt}Published 11th December, 2014.\\
   Updated 13th May, 2016.\\
   Page {\thepage} of \pageref{LastPage}.
\end{tabulary}
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  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Sponsor}}  \\
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  \vspace{-5pt}
  %\includegraphics[width=48px,height=48px]{dave.jpeg}
  Measure your website readability!\\
  www.readability-score.com
\end{tabulary}
\end{multicols}}




\begin{document}
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% www.emerson.emory.edu/services/latex/latex_169.html
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\begin{multicols*}{2}

\begin{tabularx}{8.4cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{Explicitly render views with locals}}  \tn
\SetRowColor{white}
\mymulticolumn{1}{x{8.4cm}}{1. Go to the view, replace all `@ivar` with `var` \newline % Row Count 1 (+ 1)
2. Do the same in all partials that are called from the view and always pass the params to partials explicitly with `render "products/form", \{product: product\}` \newline % Row Count 5 (+ 4)
3. At the end of the action add an explicit render call with a full path and the locals: `render "products/new", :locals =\textgreater{} \{product: product\}` \newline % Row Count 8 (+ 3)
4. Find all controllers that were using the views/partials that you changed and apply the same.% Row Count 10 (+ 2)
} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{Extract render/redirect methods}}  \tn
\SetRowColor{white}
\mymulticolumn{1}{x{8.4cm}}{1. Identify all `render` and `redirect` calls in your controller's actions. \newline % Row Count 2 (+ 2)
2. Extract a private method for each `render` and `redirect` call you found with descriptive name that shows your intention. \newline % Row Count 5 (+ 3)
3. Find and remove any duplicated methods you might created during this refactoring in the same controller.% Row Count 8 (+ 3)
} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{Extract a Single Action Controller class}}  \tn
\SetRowColor{white}
\mymulticolumn{1}{x{8.4cm}}{1. A new route declaration above the previous (first wins) \newline % Row Count 2 (+ 2)
2. Create an empty controller which inherits from the previous \newline % Row Count 4 (+ 2)
3. Copy the action content to the new controller \newline % Row Count 5 (+ 1)
4. Remove the action from the previous controller \newline % Row Count 6 (+ 1)
5. Copy the filters/methods that are used by the action to the new controller \newline % Row Count 8 (+ 2)
6. Make the new controller inherit from the `ApplicationController` \newline % Row Count 10 (+ 2)
7. Change routes to add `except: {[}:foo\_action{]}`% Row Count 11 (+ 1)
} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{Extract routing constraint}}  \tn
\SetRowColor{white}
\mymulticolumn{1}{x{8.4cm}}{1. Go to the controller, duplicate existing action method under different name. \newline % Row Count 2 (+ 2)
2. Create a constraint that can recognize which action should be called. Put it in `routes.rb` \newline % Row Count 4 (+ 2)
3. Duplicate the relevant routing rule in `routes.rb` \newline % Row Count 6 (+ 2)
4. Protect first routing rule with the constraint. \newline % Row Count 8 (+ 2)
5. Change the second routing rule so it delegates to the new controller action. If necessary, protect it with similar constraint. \newline % Row Count 11 (+ 3)
6. Remove the irrelevant code from controller actions. Make them do only one thing. \newline % Row Count 13 (+ 2)
7. (Optionally) Move the constraint(s) to separate file(s).% Row Count 15 (+ 2)
} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{Extract a repository object}}  \tn
\SetRowColor{white}
\mymulticolumn{1}{x{8.4cm}}{1. Create a class called `ProductsRepository` inside the same file as the controller \newline % Row Count 2 (+ 2)
2. Find all calls to typical \seqsplit{`Product.find/all/new/save/create`} methods in the controller \newline % Row Count 4 (+ 2)
3. Create those methods in the repo object \newline % Row Count 5 (+ 1)
4. Add a private method, called repo in the controller (possibly in the `ApplicationController`) where you instantiate the repo. \newline % Row Count 8 (+ 3)
5. Move the repository class to `app/repos/`% Row Count 9 (+ 1)
} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{Extract a service object using the SimpleDelegator}}  \tn
\SetRowColor{white}
\mymulticolumn{1}{x{8.4cm}}{1. Move the action definition into new class and inherit from `SimpleDelegator`. \newline % Row Count 2 (+ 2)
2. Step by step bring back controller responsibilities into the controller. \newline % Row Count 4 (+ 2)
3. Remove inheriting from `SimpleDelegator`. \newline % Row Count 5 (+ 1)
4. (Optional) Use exceptions for control flow in unhappy paths.% Row Count 7 (+ 2)
} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
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\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{Extract an adapter object}}  \tn
\SetRowColor{white}
\mymulticolumn{1}{x{8.4cm}}{1. Extract external library code to private methods of your controller \newline % Row Count 2 (+ 2)
2. Parametrize these methods - remove explicit request / params / session statements \newline % Row Count 4 (+ 2)
3. Pack return values from external lib calls into simple data structures. \newline % Row Count 6 (+ 2)
4. Create an adapter class inside the same file as the controller \newline % Row Count 8 (+ 2)
5. Move newly created controller methods to adapter (one by one), replace these method calls with calls to adapter object \newline % Row Count 11 (+ 3)
6. Pack exceptions raised by an external library to your exceptions \newline % Row Count 13 (+ 2)
7. Move your adapter to another file (ex. \seqsplit{app/adapters/your\_adapter}.rb)% Row Count 15 (+ 2)
} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}


% That's all folks
\end{multicols*}

\end{document}